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Secondary organic aerosol (SOA) is an important contributor to organic aerosol (OA), however, the model simulations of SOA concentrations and oxidation states remain significant uncertainties because of inadequate cognition of its formation and aging chemistry. In this study, SOA formation and evolution processes during summer in Xi'an were investigated, based on high-resolution online measurements of non-refractory PM 2.5 (NR-PM 2.5) species and OA source apportionment using positive matrix factorization. The results showed that the total SOA, including less oxidized-oxygenated OA (LO-OOA), more oxidized-oxygenated OA (MO-OOA), and aqueous-phase-processed oxygenated OA (aq-OOA), on average constituted 69% of OA, and 43% of NR-PM 2.5 , suggesting the high atmospheric oxidation capacity and the dominance of SOA during summer in Xi'an. Photochemical oxidation processes dominated the summertime SOA formation both during non-fog-rain days and fog-rain days, which were responsible for the formation of both LO-OOA and MO-OOA. Consistently, LO-OOA and MO-OOA in total contributed 59% to OA during non-fog-rain days and 56% to OA during fog-rain days, respectively. On the contrary, aq-OOA was mainly observed during fog-rain days, which increased dramatically from 2% of OA during non-fog-rain days to 19% of OA during fog-rain days with the mass concentration increasing accordingly from 0.3 μg m−3 to 2.5 μg m−3. Episodic analyses further highlighted the persistently high RH period with high aerosol liquid water content (ALWC) was the driving factor of aq-OOA formation, and high O x condition could further enhance its formation. Meanwhile, air masses from east and southeast were much favorable for the formation of long-time fog-rain days, which facilitated aq-OOA production during summer in Xi'an. Unlabelled Image • Photochemical oxidation dominated the summertime SOA formation. • The contribution of aq-OOA to total OA increased dramatically during fog-rain days. • Persistently high RH/ALWC was the driving factor of aq-OOA formation. • High O x condition could further enhance the aq-OOA production. [ABSTRACT FROM AUTHOR]

Organic aerosol (OA) is a major component of fine particulate matter (PM); however, only 10%–30% of OA have been identified as individual compounds, and some are used as markers to trace the sources and formation mechanisms of OA. The temporal and spatial coverage of these OA markers nonetheless remain inadequately characterized. This study presents a year-long measurement of 92 organic markers in PM 2.5 samples collected at an urban site in Beijing from 2014 to 2015. Saccharides were the most abundant (340.1 ng m−3) species detected, followed by phthalic acids (283.4 ng m−3). In summer, high proportions (8%–24%) of phthalic acids, n-alkanes, fatty acids, and n-alcohols indicate dominant contributions of biogenic emission and atmospheric oxidation to OA in Beijing. In winter, when anthropogenic sources prevail, saccharides, polycyclic aromatic hydrocarbons, and hopanes are more prominent (4%–25%). The spatial distributions of these OA markers in China show higher concentrations in northern cities (mainly from coal combustion and biomass burning) than in southern cities (mainly from vehicular emission). The inter-annual variations of OA markers, except for hopanes, from 2001 to 2015 suggest significant alleviation of the primary OA pollution in Beijing, with an average reduction of 35%–89% compared with those before 2008. The diagnostic ratio analyses between OA markers indicate that contributions from coal combustion and biomass burning decreased, whereas those from vehicular emission increased. Increasingly large vehicle fleets have increased hopane concentrations since 2008, but the levels were 35% lower in 2015 than those in 2010–2011 because of the tightening of emission controls for vehicles. This study provides a long-term and geographical comparison (from Beijing to other locations in China and beyond) of OA markers, demonstrating the temporal and spatial variations in primary OA, and calls for more studies on secondary OA. Unlabelled Image • The levels of OA markers are 1.3–43.2 times higher in winter than in summer. • Anthropogenic sources prevail in urban Beijing, especially in winter. • The concentrations of OA markers are generally higher in northern China. • The emission controls significantly alleviate the primary OA pollution. • A long-term and geographical comparison of OA markers are provided. [ABSTRACT FROM AUTHOR]

The Guanzhong basin is a part of the three top priority regions in China's blue sky action as of 2019. Understanding the chemical composition, sources, and atmospheric process of aerosol in this region is therefore imperative for improving air quality. In this study, we present, for the first time, the seasonal variations of organic aerosol (OA) in Xi'an, the largest city in the Guanzhong basin. Biomass burning OA (BBOA) and oxidized OA (OOA) contributed >50% of OA in both autumn and winter. The average concentrations of BBOA in autumn (14.8 ± 5.1 μg m−3) and winter (11.6 ± 6.8 μg m−3) were similar. The fractional contribution of BBOA to total OA, however, decreased from 31.9% in autumn to 15.3% in winter, because of enhanced contributions from other sources in winter. The OOA fraction in OA increased largely from 20.9% in autumn to 34.9% in winter, likely due to enhanced emissions of precursors and stagnant meteorological conditions which facilitate the accumulation and secondary formation. A large increase in OOA concentration was observed during polluted days, by a factor of ~4 in autumn and ~6 in winter compared to clean days. In both seasons, OOA formation was most likely dominated by photochemical oxidation when aerosol liquid water content was <30 μg m−3 or by aqueous-phase processes when O x was <35 ppb. A higher concentration of BBOA was observed for air masses circulated within the Guanzhong basin (16.5–18.1 μg m−3), compared to air masses from Northwest and West (10.9–14.5 μg m−3). Furthermore, compared with OA fraction in non-refractory PM 1 in other regions of China, BBOA (17–19%) and coal combustion OA (10–20%) were major emission sources in the Guanzhong Basin and the BTH region, respectively, whereas OOA (10–34%) was an important source in all studied regions. Unlabelled Image • Biomass burning and secondary formation dominated OA in both autumn and winter in Xi'an. • OOA formation was dominated by photochemical or aqueous-phase processes under different conditions. • BBOA and CCOA were major sources in the Guanzhong Basin and the BTH region, respectively. [ABSTRACT FROM AUTHOR]

• Nitrate contribution overwhelms sulfate. • Secondary formation dominates in OA in all seasons. • The formation mechanisms of SOA differ in different seasons. • Highly oxidized organic aerosol dominates in SOA irrespective of the pollution level. To mitigate air pollution in China, a legislative 'Air Pollution Prevention and Control Action Plan' has been implemented by the Chinese government since 2013. There is, however, a lack of investigations for long-term trends in the composition, sources and evolution processes of PM 1 (particulate matter with diameter less than 1 μm) after the implementation. To evaluate the effectiveness of these control measures, we present a year-long real-time measurement of the chemical composition of PM 1 at an urban site in Beijing from November 2014 to November 2015, and the results are compared with previous studies from 2008 to 2013 to gain insights into the variations of the chemical composition and sources of PM 1 in Beijing. Large seasonal differences were observed in the mass concentrations of PM 1 species and general declining trend was observed in the last seven years. Specifically, the annual averages of mass concentrations in 2014–2015 decrease by 16–43% (PM 1), 23–43% (organic aerosol, OA), 38–68% (sulfate), 26–51% (nitrate), 18–33% (ammonium) and 27–38% (chloride) compared to those from 2008 to 2013. During winter and summer, the seasonal mass concentrations of sulfate and nitrate show more significant declines especially in summer 2008 (79% and 81%) and summer 2011 (76% and 77%). The nitrate-to-sulfate ratio is higher in 2014–2015 (1.5 ± 0.6) than that in 2013 (1.0 ± 0.3), largely due to significant reduction in SO 2 emissions, suggesting that nitrate is becoming more important than sulfate in particulate pollution in Beijing. OA is the dominant PM 1 fraction (>45%) in all seasons and the mass concentrations/contributions of both primary and secondary OA show different seasonality. As for the more oxidized oxygenated OA (MO-OOA) and less oxidized oxygenated OA (LO-OOA), the contributions of MO-OOA are much higher than those of LO-OOA (27–62% vs. 6–26%) in both high-pollution and low-pollution days. Aqueous-phase processes are found to facilitate the formation of MO-OOA while photochemical oxidation formation is a major contributor of LO-OOA in winter, and photochemical oxidation plays a major role in the formation of MO-OOA in summer and fall. The current study provides a comprehensive seasonal comparison of chemical composition and formation of PM 1 in Beijing and a pacesetter in tackling PM pollution for other equally polluted megacities, after implementation of more stringent control measures after 2013. [ABSTRACT FROM AUTHOR]

Sulfate and nitrate from secondary reactions remain as the most abundant inorganic species in atmospheric particle matter (PM). Their formation is initiated by oxidation (either in gas phase or particle phase), followed by neutralization reaction primarily by NH 3 , or by other alkaline species such as alkaline metal ions if available. The different roles of NH 3 and metal ions in neutralizing H 2 SO 4 or HNO 3 , however, are seldom investigated. Here we conducted semi-continuous measurements of SO 4 2−, NO 3 −, NH 4 +, and their gaseous precursors, as well as alkaline metal ions (Na+, K+, Ca2+, and Mg2+) in wintertime Beijing. Analysis of aerosol acidity (estimated from a thermodynamic model) indicated that preferable sulfate formation was related to low pH conditions, while high pH conditions promote nitrate formation. Data in different mass fraction ranges of alkaline metal ions showed that in some ranges the role of NH 3 was replaced by alkaline metal ions in the neutralization reaction of H 2 SO 4 and HNO 3 to form particulate SO 4 2− and NO 3 −. The relationships between mass fractions of SO 4 2− and NO 3 − in those ranges of different alkaline metal ion content also suggested that alkaline metal ions participate in the competing neutralization reaction of sulfate and nitrate. The implication of the current study is that in some regions the chemistry to incorporate sulfur and nitrogen into particle phase might be largely affected by desert/fugitive dust and sea salt, besides NH 3. This implication is particularly relevant in coastal China and those areas with strong influence of dust storm in the North China Plain (NCP), both of which host a number of megacities with deteriorating air quality. Unlabelled Image • Alkaline metal ions compete with NH 3 in the neutralization of sulfate and nitrate. • Increased sulfate was related to low pH, while high pH promotes nitrate formation. • In some regions the sulfate/nitrate formation might be largely affected by dust. [ABSTRACT FROM AUTHOR]

The contributions of chemical composition and emission sources to aerosol optical properties were evaluated for a coastal city in southern China. The average dry light scattering coefficient (b scat,dry) and light absorption coefficient (b abs) were 32.5 ± 15.5 Mm−1 and 8.8 ± 4.7 Mm−1, respectively. Diurnal cycles in b scat,dry and b abs were observed with peak values in the morning and at night. Both b scat,dry and b abs varied with wind speeds and directions, and thus affected by transport pathways. Chemical composition data for 12-h PM 2.5 samples were used with the revised IMPROVE algorithm and a Hybrid Environmental Receptor Model to evaluate aerosol composition and source contributions to dry light extinction (b ext,dry = b scat,dry + b abs), respectively. Ammonium sulfate and organic matter were the dominant contributors to b ext,dry , followed by elemental carbon, sea salt, fine soil, and ammonium nitrate. The six PM 2.5 sources identified were secondary sulfate source, biomass burning, marine emission, fugitive dust, traffic-related emission, and shipping emission. Marine emission and secondary sulfate source were the largest contributors of b ext,dry during the daytime and nighttime, respectively. Backward trajectory analysis further explored the impact of potential sources to b ext,dry at Sanya from surrounding regions. The results of our study would be useful for improving models of radiative effects from different sources in this area. Unlabelled Image • The lower b scat,dry and b abs were consistent with better air quality at Sanya. • Ammonium sulfate and organic matter contributed most to b ext,dry. • Source contributions to b ext,dry changed from the daytime to the nighttime. • Much higher contribution of biomass burning to b ext,dry was found from Southeast Asia. [ABSTRACT FROM AUTHOR]

Micromonospora carbonacea JXNU-1, a strain of an actinomycete with broad-spectrum antimicrobial activity, isolated from soil samples from the farmland in the area of Yaohu Lake in Nanchang, China, was taken as the object of study in this paper. Bioinformatics analysis revealed that there was a pair of proteins MCNtrB/MCNtrC homologous to the two-component system NtrB/NtrC, which usually exists only in the Gram-negative bacteria and is closely related to the regulation of nitrogen metabolism, in the whole cell protein of M. carbonacea. MCNtrB and MCNtrC, obtained by expression in vitro, were subjected to autophosphorylation and phosphate group transfer experiments. The results showed that MCNtrB had histidine kinase activity with the active site of His115, and MCNtrC can accept the phosphate group from phosphorylated MCNtrB with the active site of Asp33. The yeast two-hybrid experiments showed that MCNtrB and MCNtrC were a pair of proteins with a strong interaction. Overexpression of MCNtrB and MCNtrC in M. carbonacea can affect the expression of key enzymes in cellular nitrogen metabolism, such as glutamine synthetase, glutamate synthase, and glutamate dehydrogenase. These results indicated that MCNtrB/MCNtrC is a two-component system related to nitrogen metabolism in M. carbonacea, which could provide an important experimental basis for revealing the regulatory mechanism of nitrogen metabolism in M. carbonacea., (© The Author(s) 2025. Published by Oxford University Press on behalf of FEMS.)

The study was designed to appraise the effects of early antibiotic administration on reproductive tract infections and fetal membrane cell scorching in instances of premature rupture of membranes (PROM). A total of 107 pregnant women diagnosed with PROM between July 2020 and June 2022 were randomly assigned to two groups: the Intervention (n=54), where ampicillin were administered within 24 hours of PROM onset, and the control group (n=53), where ampicillin were given 24-48 hours after PROM. Maternal and neonatal outcomes, incidence of reproductive tract infections, and fetal membrane cell scorching indicators (Caspase-1, Caspase -3, Caspase-9 and IL-β) were compared. The intervention group had significantly fewer adverse maternal and neonatal outcomes (p<0.05). Post-treatment, rates of Chlamydia trachomatis, Mycoplasma solium, and genital tract infections decreased in both groups, with lower rates in the intervention group (p<0.05). Positive expression rates of Caspase-1, -3, -9, and IL-β in placental tissues were also lower in the intervention group (p<0.05). We conclude that administering antibiotics within 12 hours of PROM reduces reproductive tract infections, lowers fetal membrane cell scorching, and improves maternal and neonatal outcomes, supporting early antibiotic use in the management of PROM., Competing Interests: The Authors declared no conflict of interest, (African Journal of Reproductive Health © 2024.)

Poyang Lake is the largest freshwater lake in China, which boasts unique hydrological conditions and rich biodiversity. In this study, metagenomics technology was used to sequence the microbial genome of soil samples S1 (sedimentary), S2 (semi-submerged), and S3 (arid) with different water content from the Poyang Lake wetland; the results indicate that the three samples have different physicochemical characteristics and their microbial community structure and functional gene distribution are also different, resulting in separate ecological functions. The abundance of typical ANME archaea Candidatus Menthanoperedens and the high abundance of mcrA in S1 mutually demonstrate prominent roles in the methane anaerobic oxidation pathway during the methane cycle. In S2, the advantageous bacterial genus Nitrospira with ammonia oxidation function is validated by a large number of nitrification functional genes ( amoA, hao, nxrA ), manifesting in that it plays a monumental role in nitrification in the nitrogen cycle. In S3, the dominant bacterial genus Nocardioides confirms a multitude of antibiotic resistance genes, indicating their crucial role in resistance and their emphatic research value for microbial resistance issues. The results above have preliminarily proved the role of soil microbial communities as indicators predicting wetland ecological functions, which will help to better develop plans for restoring ecological balance and addressing climate change.

A promising approach to prevent heat- and cold-related illnesses is the integration of zero-energy input control technology into personal thermal management (PTM) systems while reducing energy consumption. However, achieving optimal wearing comfort while maintaining subambient metabolic temperatures using thermally regulating materials without an energy supply remains challenging. In this study, we provide a simple and reliable methodology to produce a phase-changeable metafabric made of thermoplastic polyurethane and phase change capsule (PCC) particles with high moisture permeability and thermal comfort. This approach skillfully incorporates spray-formed PCC particles into a three-dimensional nanofibrous aggregate, forming a stable self-entangled network structure in a single step through simultaneous humidity-assisted electrospraying and electrospinning processes. Additionally, the metafabric demonstrates prominent water resistance and superhydrophobicity, which are attributed to the integration of PCC particles and nanofibers, resulting in the formation of a microporous/nanoporous structure resembling the surface of a lotus leaf. As a result, the phase-changeable metafabric shows an active and passive thermal control performance, with a water vapor transmittance rate of 13.1 kg m -2 d -1 and a phase change enthalpy of 115.05 J g -1 even after 100 thermal cycles. Furthermore, it displays excellent waterproofing capability, characterized by a water contact angle of 158.7° and the ability to withstand a high hydrostatic pressure of 87 kPa. In addition, the metafabric exhibits a good mechanical performance, boasting a tensile strength of 10.5 MPa. Overall, the proposed economical metafabric is an exemplary candidate material for next-generation PTM systems.

The Tibetan Plateau, known as the "Third Pole", is susceptible to ground-level ozone (O 3 ) and fine particulate matter (PM 2.5 ) pollution due to its unique high-altitude environment. This study constructed random forest regression models using multi-source data from ground measurements and meteorological satellites to predict variations in ground-level O 3 and PM 2.5 concentrations and their influencing factors across seven major cities in the Tibetan Plateau over two-year periods. The models successfully reproduced O 3 and PM 2.5 levels with satisfactory R-squared values of 0.71 and 0.73, respectively. Results reveal combustion-related carbon monoxide (CO) and nitrogen dioxide (NO 2 ) as the most substantial influences on O 3 and PM 2.5 concentrations. Solar radiation, geographical factors, and meteorological variables also played crucial roles in driving pollutant variations. Conversely, transport-related and human activity factors exhibited relatively lower significance. High O 3 and PM 2.5 pollution occurred during pre-monsoon and post-monsoon/winter seasons, driven by solar radiation and emissions, respectively. While CO consistently contributed across cities and seasons, key influencing factors varied locally. This study unveils the key driving forces governing air pollutant variations across the Tibetan Plateau, shedding light on complex atmospheric processes in this unique high-altitude region., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

A Gram-stain-positive, rod-shaped, non-spore-forming and non-motile bacterium, designated strain WY-16 T . Growth was observed at 20-42 °C (optimum, 30 °C), pH 6-9 (optimum, pH 7) and salinity of 0-3 % (w/v; optimum, 1 %). Phylogenetic analysis based on genome sequences indicated that WY-16 T was affiliated to the family Microbacteriaceae and most closely related to Salinibacterium xinjiangense and Salinibacterium amurskyense . The average nucleotide identity values between strain WY-16 T and S. xinjiangense and S. amurskyense were 74.7 and 72.5 %, respectively. The digital DNA-DNA hybridization values between strain WY-16 T and S. xinjiangense and S. amurskyense were 19.6 and 18.6 %, respectively. The predominant fatty acids were anteiso-C 15 : 0 , iso-C 16 : 0 and iso-C 16 : 0 10-methyl. The major menaquinones were MK-12, MK-13, MK-14 and MK-15. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, one unidentified glycolipid and one unidentified phospholipid. The cell-wall peptidoglycan contained 2,4-diaminobutyric acid as the diamino acid and ribose, rhamnose, glucose and galactose were the major cell-wall sugars. Based on phenotypic, genotypic and phylogenetic evidence, strain WY-16 T represents a novel species in the genus Salinibacterium , for which the name Salinibacterium soli sp. nov. is proposed. The type strain is WY-16 T (=GDMCC 1.4011 T =JCM 36421 T ).

Translation elongation factor P, expressed by the efp gene, is a conserved protein closely related to bacterial virulence and environmental stress regulation responses, however, little is known about the efp gene expression regulations. Here, the strain of Staphylococcus aureus subsp. aureus NCTC 8325 was taken as the research object and cultured under different conditions, including different culture temperatures, pH, and antibiotics, to study the expression of the efp gene in S. aureus by qRT-PCR, the results showed that the expression of the efp gene is upregulated under high temperature (40 °C), acidic (pH 5.4) or alkaline (pH 9.4) culture conditions, but upregulated early and downregulated later under the conditions of 0.5 MIC antibiotics (chloramphenicol at the final concentration of 2 μg/mL and vancomycin at the final concentration of 0.25 μg/mL), indicating that the efp promoter in S. aureus is inducible. The efp promoter sequence and structure in S. aureus were predicted by bioinformatics methods, and the predicted promoter was validated by constructing a promoter-probe vector and a series of promoter mutants, the results showed that the efp promoter sequence in S. aureus, named Pro, located in 1,548,179-1,548,250 of the S. aureus genome (NC&#95;007795.1), and the sequence of - 10 element is CCTTATAGT, - 35 element is TTTACT. The results above could lay a foundation for screening transcription factors involved in the expression of the efp gene and then exploring the transcriptional regulation mechanism of EF-P in S. aureus., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

To explore the mechanism of necrotic effect of nourishing cells in the context of genital tract infection in premature rupture of membranes (PROM). One hundred eight patients with PROM treated at our hospital from June 2020 to June 2022 were selected as the PROM group. Simultaneously, 108 cases of normal full-term pregnant women were chosen as the control group. Western blot analysis was performed to measure the relative expression levels of cysteinyl aspartate specific proteinase-1 (Caspase-1), cysteinyl aspartate specific proteinase-3 (Caspase-3), nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3), and interleukin (IL)-1β proteins, which are associated with necrosis of placental nourishing cells, in the placenta of both groups. TUNEL staining was used to detect the number of apoptotic placental nourishing cells. The differences in necrotic factors of placental nourishing cells were analyzed between full-term and preterm cases in the PROM group, as well as among patients with different genital tract infections. The apoptotic count of placental nourishing cells in the PROM group was 58.46 ± 11.26 cells/field, which was markedly higher than that of the control group (P < .05). The relative expression levels of the necrotic factors Caspase-1, Caspase-3, NLRP3, and IL-1β proteins in placental nourishing cells of the PROM group were 1.32 ± 0.26, 1.19 ± 0.30, 1.29 ± 0.28, and 1.23 ± 0.24, respectively. These values were significantly higher than those of the control group (P < .05). The relative expression levels of the necrotic factors Caspase-1, Caspase-3, NLRP3, and IL-1β proteins in placental nourishing cells were compared between full-term and preterm patients in the PROM group (P > .05). The relative expression levels of the necrotic factors Caspase-1, Caspase-3, NLRP3, and IL-1β proteins in placental nourishing cells were higher in patients with multiple genital tract infections compared to those with single infections or no infections in the PROM group (P < .05). PROM is associated with a significant upregulation of placental nourishing cell apoptosis and necrotic factors, including Caspase-1, Caspase-3, NLRP3, and IL-1β proteins. This upregulation is correlated with the presence of genital tract infections., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2023 the Author(s). Published by Wolters Kluwer Health, Inc.)

Methylsiloxanes have gained growing attention as emerging pollutants due to their toxicity to organisms. As man-made chemicals with no natural source, most research to date has focused on volatile methylsiloxanes from personal care or household products and industrial processes. Here, we show that methylsiloxanes can be found in primary aerosol particles emitted by vehicles based on aerosol samples collected in two tunnels in São Paulo, Brazil. The aerosol samples were analyzed with thermal desorption-proton transfer reaction-mass spectrometry (TD-PTR-MS), and methylsiloxanes were identified and quantified in the mass spectra based on the natural abundance of silicon isotopes. Various methylsiloxanes and derivatives were found in aerosol particles from both tunnels. The concentrations of methylsiloxanes and derivatives ranged 37.7-377 ng m -3 , and the relative fractions in organic aerosols were 0.78-1.9%. The concentrations of methylsiloxanes exhibited a significant correlation with both unburned lubricating oils and organic aerosol mass. The emission factors of methylsiloxanes averaged 1.16 ± 0.59 mg kg -1 of burned fuel for light-duty vehicles and 1.53 ± 0.37 mg kg -1 for heavy-duty vehicles. Global annual emissions of methylsiloxanes in vehicle-emitted aerosols were estimated to range from 0.0035 to 0.0060 Tg, underscoring the significant yet largely unknown potential for health and climate impacts.

Microbial reduction is an effective way to deal with hexavalent chromium [Cr(VI)] contamination in the environment, which can significantly mitigate the biotoxicity and migration of this pollutant. The present study investigated the influence of environmental factors on aqueous Cr(VI) removal by a newly isolated facultative anaerobic bacterium, Exiguobacterium sp. PY14, and revealed the reduction mechanism. This strain with a minimum inhibitory concentration of 400 mg/L showed the strongest Cr(VI) removal capacity at pH 8.0 because of its basophilic nature, which was obviously depressed by increasing the Cr(VI) initial concentration under both aerobic and anaerobic conditions. In contrast, the removal rate constant for 50 mg/L of Cr(VI) under anaerobic conditions (1.82 × 10 -2 h -1 ) was 3.3 times that under aerobic conditions. The co-existence of Fe(III) and Cu(II) significantly promoted the removal of Cr(VI), while Ag(I), Pb(II), Zn(II), and Cd(II) inhibited it. Electron-shuttling organics such as riboflavin, humic acid, and anthraquinone-2,6-disulfonate promoted the Cr(VI) removal to varying degrees, and the enhancement was more significant under anaerobic conditions. The removal of aqueous Cr(VI) by strain PY14 was demonstrated to be due to cytoplasmic rather than extracellular reduction by analyzing the contributions of different cell components, and the end products existed in the aqueous solution in the form of organo-Cr(III) complexes. Several possible genes involved in Cr(VI) metabolism, including chrR and chrA that encode well-known Chr family proteins responsible for chromate reduction and transport, respectively, were identified in the genome of PY14, which further clarified the Cr(VI) reduction pathway of this strain. The research progress in the influence of crucial environmental factors and biological reduction mechanisms will help promote the potential application of Exiguobacterium sp. PY14 with high adaptability to environmental stress in Cr(VI) removal in the actual environment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Huang, Tang, Zhang, Long, Ni, Fu and Zou.)

A Gram-stain-negative, rod-shaped, polar flagellated or stalked and non-spore-forming bacterium, designated LB-2 T , was isolated from activated sludge. Growth was observed at 20-30 °C (optimum 28 °C), pH 6.0-8.0 (optimum pH 7.0) and salinity of 0-0.5% (w/v; optimum 0.5%). Phylogenetic analysis based on the 16S rRNA gene indicated that strain LB-2 T belongs to the genus Sphingomonas and showed the highest sequence similarity (96.7%) and less than 96.7% similarities to other type strains. The genome size of strain LB-2 T was 4.10 Mb, with 66.8 mol% G + C content. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strains LB-2 T and S. canadensis FWC47 T were 77.8% and 21%, respectively. The predominant cellular fatty acids were summed feature 8 (C 18:1 ω7c and/or C 18 : 1 ω6c) and C 16:0 . The major polar lipids were aminolipid, glycolipid, sphingoglycolipid, phosphatidylcholine, phosphatidylglycerol, four unidentified lipids, glycophospholipid, phosphatidylethanolamine and diphosphatidylglycerol. The predominant respiratory quinone was Q-10 and the major polyamine was sym-homospermidine. On the basis of phenotypic, genotypic and phylogenetic evidences, strain LB-2 T represents a novel species in the genus Sphingomonas, for which the name Sphingomonas caeni sp. nov. is proposed. The type strain is LB-2 T (GDMCC 1.3630 T  = NBRC 115,102 T )., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The you-only-look-once (YOLO) model identifies objects in complex images by framing detection as a regression problem with spatially separated boundaries and class probabilities. Object detection from complex images is somewhat similar to underwater source detection from acoustic data, e.g., time-frequency distributions. Herein, YOLO is modified for joint source detection and azimuth estimation in a multi-interfering underwater acoustic environment. The modified you-only-look-once (M-YOLO) input is a frequency-beam domain (FBD) sample containing the target and multi-interfering spectra at different azimuths, generated from the received data of a towed horizontal line array. M-YOLO processes the whole FBD sample using a single-regression neural network and directly outputs the target-existence probability and spectrum azimuth. Model performance is assessed on both simulated and at-sea data. Simulation results reveal the strong robustness of M-YOLO toward different signal-to-noise ratios and mismatched ocean environments. As tested on the data collected in an actual multi-interfering environment, M-YOLO achieved near-100% target detection and a root mean square error of 0.54° in azimuth estimation., (© 2023 Acoustical Society of America.)

Glyoxal (Gly) and methylglyoxal (Mgly) are key precursors globally for secondary organic aerosol (SOA) formation. These two species were often thought to be formed in the atmosphere via photochemical oxidation of organics from biogenic and anthropogenic origins, although few studies have shown their direct emissions. In this study, we report direct emissions of particulate Gly and Mgly from different residential fuels typically used in north China. The emission ratios (ERs) and emission factors (EFs) of particulate Gly and Mgly for biomass burning were approximate 5-fold and 7-fold higher than those for coal combustion, respectively. The large variances in emissions of Gly and Mgly could be attributed to the different combustion processes, which influenced by the fuel types and combustion conditions. The averaged ERs and EFs of particulate Gly and Mgly were about one order of magnitude lower than their gaseous counterparts due to the low Henry's law constant, which was also consistent with the low particle-to-gas ratio of Gly (0.04) and Mgly (0.02). Our results suggest that the direct emissions of Gly and Mgly from emission sources should be considered when estimating the formation of SOA from Gly and Mgly., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The health effects of trace metal elements in atmospheric fine particulate matter (PM 2.5 ) are widely recognized, however, the emission factor profiles and chemical fractionation of metal elements in different sources were poorly understand. In this study, sixteen metal elements, including Cd, Pb, V, Zn, Ba, Sb, As, Fe, Sr, Cr, Rb, Co, Mn, Cu, Ni and Sn from biomass burning, bituminite and anthracite combustion, as well as dust, were quantified. The results show different emission sources were associated with distinct emission profiles, holding important implications for source apportionment of ambient particulate metals. Specifically, Fe was the dominant metal species (28-1922 mg/kg) for all samples, and was followed by different metals for different samples. For dust, Mn (39.9 mg/kg dust ) had the second-highest emission factor, while for biomass burning, it was Cr and Ba (7.5 and 7.4 mg/kg biomass , respectively). For bituminous coal combustion, the emission factor of Zn and Ba was 6.2 and 6.0 mg/kg bituminous , respectively, while for anthracite combustion the corresponding emission factor was 5.6 and 4.3 mg/kg anthracite , respectively. Moreover, chemical fractionation (i.e., the exchangeable, reducible fraction, oxidizable, and residual fraction) and the bioavailability index (BI) values of the metal elements from different sources were further investigated to reveal the link between different emission sources and the potential health risk. The findings from this study hold important implications for source apportionment and source-specific particulate metal-associated health effects., (Copyright © 2021. Published by Elsevier B.V.)

Carbon isotope signatures are used to gain insight into sources and atmospheric processing of carbonaceous aerosols. Since elemental carbon (EC) is chemically stable, it is possible to apportion the main sources of EC (C3/C4 plant burning, coal combustion, and traffic emissions) using a dual 14 C- 13 C isotope approach. The dual-isotope source apportionment crucially relies on accurate knowledge of 13 C source signatures, which are seldom measured for EC. In this work, we present 13 C signatures of organic carbon (OC) and EC for relevant sources in China. EC was isolated for 13 C analysis based on the OC/EC split point of a thermal-optical method (EUSAAR&#95;2 protocol). A series of sensitivity studies were conducted to investigate the EC separation and the relationship of the thermal-optical method to other EC isolation methods. Our results show that, first, the 13 C signatures of raw materials and EC related to traffic emissions can be separated into three groups according to geographical location. Second, the 13 C signature of OC emitted by the flaming combustion of C4 plants is strongly depleted in 13 C compared to the source materials, and therefore EC is a better tracer for this source than total carbon (TC). A comprehensive literature review of 13 C source signatures (of raw materials, of TC, and of EC isolated using a variety of thermal methods) was conducted. Accordingly, we recommend composite 13 C source signatures of EC with uncertainties and detailed application conditions. Using these source signatures of EC in an example dual-isotope source apportionment study shows an improvement in precision. In addition, 13 C signatures of OC were measured at three different desorption temperatures roughly corresponding to semi-volatile, low-volatile, and non-volatile OC fractions. Each source category shows a characteristic trend of 13 C signatures with desorption temperature, which is likely related to different OC formation processes during combustion., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Microbially driven iron and sulfur geochemical cycles co-exist ubiquitously in subsurface environments and are of environmental relevance. Shewanella species (dissimilatory metal-reducing bacteria) are capable of reducing Fe(III)-(oxyhydr)oxide minerals and diverse sulfur sources using corresponding metabolic pathways and producing FeS secondary minerals. In spite of the ability in promoting bacterial extracellular electron transfer (EET), the specific role of FeS in mediating EET between microbe/mineral interface is still unclear. In this work, the electron-mediating function of biogenic FeS on promoting the reduction of ferrihydrite by S. oneidensis MR-1 using thiosulfate as sulfur source was investigated in terms of Fe(III) reduction percentage, X-ray diffraction and scanning electron microscopy. The results showed that the microbial ferrihydrite reduction was pH-dependent and positively correlated with the addition of thiosulfate. In the presence of thiosulfate, biogenic FeS in nano-scale were formed and deposited on the surfaces of S. oneidensis MR-1 and ferrihydrite to build an interfacial electron transfer bridge between them. The addition of either thiosulfate and in-vitro FeS could rescue the entirely inactivated ability of the mutant (△omcA/mtrC) in ferrihydrite reduction to some extent, but which was obviously inferior to the wild-type strain. Meanwhile, the effect of the biogenic FeS in-situ coating on the surfaces of S. oneidensis MR-1 cells on promoting microbial ferrihydrite reduction was significantly superior to the in-vitro ones. Thus, the in-situ formed biogenic FeS secondary minerals were demonstrated to mediate and accelerate interfacial electron transfer from S. oneidensis MR-1 cells to ferrihydrite through interfacing with the bacterial EET routes, especially Mtr pathway. This work provides an insight into the secondary minerals-mediating interfacial electron transfer between microbes and minerals in the presence of biological S (-II), which has important biogeochemical and environmental implications., (Copyright © 2021. Published by Elsevier Ltd.)

We describe and thoroughly evaluate a method for 13 C analysis in different fractions of carbonaceous aerosols, especially elemental carbon (EC). This method combines a Sunset thermal-optical analyzer and an isotope ratio mass spectrometer (IRMS) via a custom-built automated separation, purification, and injection system. Organic carbon (OC), EC, and other specific fractions from aerosol filter samples can be separated and analyzed automatically for 13 C based on thermal-optical protocols (EUSAAR&#95;2 in this study) at sub-μgC levels. The main challenges in isolating EC for 13 C analysis are the possible artifacts during OC/EC separation, including the premature loss of EC and the formation of pyrolyzed OC (pOC) that is difficult to separate from EC. Since those artifacts can be accompanied with isotope fractionation, their influence on the stable isotopic composition of EC was comprehensively investigated with various test compounds. The results show that the thermal-optical method is relatively successful in OC/EC separation for 13 C analysis. The method was further tested on real aerosols samples. For biomass-burning source samples, (partial) inclusion of pOC into EC has negligible influence on the 13 C signature of EC. However, for ambient samples, the influence of pOC on the 13 C signature of EC can be significant, if it is not well separated from EC, which is true for many current methods for measuring 13 C on EC. A case study in Xi'an, China, where pOC is enriched in 13 C compared to EC, shows that this can lead to an overestimate of coal and an underestimate of traffic emissions in isotope-based source apportionment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

This study investigates the sources and atmospheric processes of size-resolved carbonaceous aerosols in winter 2018 in urban Beijing, based on analysis of dual-carbon isotopes (i.e., radiocarbon and the stable isotope 13 C). We found a size dependence of fossil source contributions to elemental carbon (EC), but no clear size dependence for organic carbon (OC). Comparable fossil source contributions to water-insoluble OC (WIOC; 55 ± 3%) and to water-soluble OC (WSOC; 54 ± 4%) highlight the importance of secondary aerosol formation, considering that fossil sources emit only small amounts of primary WSOC. OC concentrations increased during high PM 2.5 pollution events, with increased fossil and non-fossil WSOC concentrating at larger particles (0.44-2.5 µm) than WIOC (0.25-2.5 µm), highlighting the aqueous-phase chemistry as an important pathway for OC production. The ratio of 13 C/ 12 C (expressed as δ 13 C) of total carbon (-27.0‰ to -23.3‰) fell in the range of anthropogenic aerosol, reflecting small biogenic influence. δ 13 C of OC increased with desorption temperature steps (200 °C, 350 °C and 650 °C). The strongly enriched δ 13 C OC,650 (-26.9‰ to -20.3‰) and large mass fraction of OC 650°C in total desorbed OC, both increasing with the increase of particle sizes, were caused by photochemical aging, especially during low and moderate PM 2.5 pollution events, when regional, aged aerosol played an important role. During low pollution events, higher δ 13 C OC,650 and WSOC/OC ratios reflect a larger contribution and more extensive chemical processing of aged aerosol. In contrast, relatively low δ 13 C OC,200 (-27.2‰ to -25.7‰) suggests the influence of secondary OC formation on the more volatile OC desorbed at 200 °C. δ 13 C OC,200 was similar for all particle sizes and for different pollution events, pointing to an internal mixture of local and aged regional OC. Our results show that the organic aerosol in Beijing arises from a mixture of various sources and complex formation processes, spanning local to regional scales. Particle sizes < 250 nm show strong contribution from local secondary OC formation, whereas refractory OC in particles around 1 µm shows strong evidence for regional aging processes. In summary, primary emission, secondary and aqueous-phase formation, and (photo-)chemical aging all need to be considered to understand organic aerosol in this region and their importance varies with particle size., (Copyright © 2021. Published by Elsevier Ltd.)

Smog chamber experiments were conducted to characterize the light absorption of brown carbon (BrC) from primary and photochemically aged coal combustion emissions. Light absorption was measured by the UV-visible spectrophotometric analysis of water and methanol extracts of filter samples. The single-scattering albedo at 450 nm was 0.73 ± 0.10 for primary emissions and 0.75 ± 0.13 for aged emissions. The light absorption coefficient at 365 nm of methanol extracts was higher than that of water extracts by a factor of 10 for primary emissions and a factor of 7 for aged emissions. This suggests that the majority of BrC is water-insoluble even after aging. The mass absorption efficiency of this BrC (MAE 365 ) for primary OA (POA) was dependent on combustion conditions, with an average of 0.84 ± 0.54 m 2 g -1 , which was significantly higher than that for aged OA (0.24 ± 0.18 m 2 g -1 ). Secondary OA (SOA) dominated aged OA and the decreased MAE 365 after aging indicates that SOA is less light absorbing than POA and/or that BrC is bleached (oxidized) with aging. The estimated MAE 365 of SOA (0.14 ± 0.08 m 2 g -1 ) was much lower than that of POA. A comparison of MAE 365 of residential coal combustion with other anthropogenic sources suggests that residential coal combustion emissions are among the strongest absorbing BrC organics.

A Gram-stain-negative, orange-colored bacterium, designated HX-22-17 T , was isolated from activated sludge of an agricultural chemical plant in Maanshan, Anhui province, China (118° 52' E 31° 68' N). The strain was strictly aerobic, non-endospore forming, non-motile, and ellipse. Growth of the strain was observed at 16-42 °C (optimum between 25 and 30 °C) at pH 6.0-9.0 (optimum at pH 7.0) and with 0-6.0% (w/v) NaCl (optimum at 1.0%). 16S rRNA gene sequence analysis showed that the strain was most closely related to Rudanella lutea KACC 12603 T (99.5% similarity). The predominant cellular fatty acids were summed feature 3 (C 16:1 ω7c and/or C 16:1 ω6c), iso-C 15:0 , and anteiso-C 15:0 . The major polar lipids included posphatidylethanolamine (PE), aminolipid (AL), and phospholipids (PL). The genomic DNA G+C content of the strain was 54.1 mol%. The ANI and dDDH values obtained between the genomes of HX-22-17 T and R. lutea KACC 12603 T were 89.3% and 39.3%, respectively. The phenotypic, chemotaxonomic, and genotypic data clearly showed that strain HX-22-17 T represents a novel species of the genus Rudanella, for which the name R. paleaurantiibacter sp. nov. is proposed. The type strain is HX-22-17 T (=KCTC 72656 T  = CCTCC AB 2019347 T ).

Topramezone is a 4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitor. Due to its broad-spectrum, high efficiency, and low toxicity, topramezone is a candidate herbicide for the construction of genetically modified (GM) herbicide-resistant crops. In the present study, we screened a topramezone-resistant isolate Sphingobium sp. TPM-19 and cloned a topramezone-resistant HPPD gene ( SphppD ) from this isolate. Sp HPPD shared the highest similarity (53%) with an HPPD from Vibrio vulnificus CMCP6. Sp HPPD was synthesized in Escherichia coli BL21(DE3) and purified to homogeneity using Co 2+ -affinity chromatography. Sp HPPD was found to be a monomer. The K m and k cat of Sp HPPD for 4-hydroxyphenylpyruvate (4-HPP) were 82.8 μM and 15.0 s -1 , respectively. Sp HPPD showed high resistance to topramezone with half maximal inhibitory concentration (IC 50 ) and K i values of 5.2 and 2.5 μM, respectively. Additionally, Sp HPPD also showed high resistance to isoxaflutole (DKN) (IC 50 : 8.7 μM; K i : 6.0 μM) and mesotrione (IC 50 : 4.2 μM; K i : 1.3 μM) and moderate resistance to tembotrione (IC 50 : 2.5 μM; K i : 1.0 μM). The introduction of the SphppD gene into Arabidopsis thaliana enhanced obvious resistance against topramezone. In conclusion, this study provides a novel topramezone-resistant HPPD gene for the genetic engineering of GM herbicide-resistant crops.

Five types of crop residue (rice, wheat, corn, sorghum, and sugarcane) collected from different provinces in China were used to characterize the chemical components and bioreactivity properties of fine particulate matter (PM 2.5 ) emissions during open-burning scenarios. Organic carbon (OC) and elemental carbon (EC) were the most abundant components, contributing 41.7%-54.9% of PM 2.5 emissions. The OC/EC ratio ranged from 8.8 to 31.2, indicating that organic matter was the dominant component of emissions. Potassium and chloride were the most abundant components in the portion of PM 2.5 composed of water-soluble ions. The coefficient of divergence ranged from 0.27 to 0.51 among various emissions profiles. All samples exposed to a high PM 2.5 concentration (150 μg/mL) exhibited a significant reduction in cell viability (A549 lung alveolar epithelial cells) and increase in lactic dehydrogenase (LDH) and interleukin 6 levels compared with those exposed to 20 or 0 μg/mL. Higher bioreactivity (determined according to LDH and interleukin 6 level) was observed for the rice, wheat, and corn samples than for the sorghum straw samples. Pearson's correlation analysis suggested that OC, heavy metals (chromium, manganese, iron, nickel, copper, zinc, tin, and barium), and water-soluble ions (fluoride, calcium, and sulfate) are the components potentially associated with LDH production., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

In this study, a bacterial strain P13 capable of degrading pendimethalin was isolated from the soil of a fruit garden. Based on observed cellular morphology and physiology characteristics and a phylogenetic analysis of 16S rRNA gene sequences, strain P13 was identified as a member of the genus Paracoccus. Strain P13 grew on pendimethalin as the sole carbon source, and could degrade 100 mg/L pendimethalin within 2 days and 200 mg/L pendimethalin within 5 days. Pendimethalin degradation was proposed to be initiated by oxidation ring cleavage to yield 1,3-dinitro-2-(pentan-3-ylamino)butane-1,4-diol, an alkane organic compound that was identified by ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS), which then underwent a series of enzymatic reactions to produce CO 2 and H 2 O. The optimal pH and temperature for pendimethalin degradation by strain P13 were 7.0 and 30 °C, respectively. This study identified the bacterial strain Paracoccus sp. P13, which degraded pendimethalin with a relatively high efficiency, and presents a previously unreported microbial pendimethalin degradation pathway.

Objectives: To characterize a novel dimethoate amidohydrolase from Sphingomonas sp. DC-6., Results: A gene, dmhA, encoding the dimethoate amidohydrolase responsible for transforming dimethoate to dimethoate carboxylic acid and methylamine, was cloned from Sphingomonas sp. DC-6. Sequence analysis and molecular modeling indicate that DmhA shares 31-57 % amino acid sequence identities with other functionally confirmed amidohydrolase. DmhA was expressed in Escherichia coli BL21 (DE3) and purified by Ni-NTA affinity chromatography. The purified DmhA could hydrolyze 4-acetaminophenol, dimethoate and propanil. DmhA activity was optimal at 30 °C and pH 7.5. Hg(2+), Zn(2+), Cu(2+), Cd(2+), Tween 80, Triton X-100 or SDS strongly inhibited its activity. The K m and k cat values of DmhA for dimethoate are 0.02 mM and 1.2 s(-1), respectively., Conclusions: DmhA was confirmed to be a novel dimethoate amidohydrolase which could eliminate the toxicity of dimethoate, providing a novel gene resource for the development of pesticide-degrading enzyme preparation and mechanistic study of dimethoate hydrolysis.

A bacterium strain Y3, capable of efficiently degrading pendimethalin, was isolated from activated sludge and identified as Bacillus subtilis according to its phenotypic features and 16S rRNA phylogenetic analysis. This strain could grow on pendimethalin as a sole carbon source and degrade 99.5% of 100mg/L pendimethalin within 2.5days in batch liquid culture, demonstrating a greater efficiency than any other reported strains. Three metabolic products, 6-aminopendimethalin, 5-amino-2-methyl-3-nitroso-4-(pentan-3-ylamino) benzoic acid, and 8-amino-2-ethyl-5-(hydroxymethyl)-1,2-dihydroquinoxaline-6-carboxylic acid, were identified by HPLC-MS/MS, and a new microbial degradation pathway was proposed. A nitroreductase catalyzing nitroreduction of pendimethalin to 6-aminopendimethalin was detected in the cell lysate of strain Y3. The cofactor was nicotinamide adenine dinucleotide phosphate (NADPH) or more preferably nicotinamide adenine dinucleotide (NADH). The optimal temperature and pH for the nitroreductase were 30°C and 7.5, respectively. Hg(2+), Ni(2+), Pb(2+), Co(2+), Mn(2+) Cu(2+), Ag(+), and EDTA severely inhibited the nitroreductase activity, whereas Fe(2+), Mg(2+), and Ca(2+) enhanced it. This study provides an efficient pendimethalin-degrading microorganism and broadens the knowledge of the microbial degradation pathway of pendimethalin., (Copyright © 2015. Published by Elsevier B.V.)

Objective: To prepare the aortic extracellular matrix (ECM) scaffold by using different methods to decellularize porcine ascending aorta and to comprehensively compare the efficiency of decellularization and the damage of ECM, evaluation of biomechanical property and biocompatibility., Methods: Thirty specimens of fresh porcine ascending aorta were randomly divided into 6 groups (n=5). The porcine ascending aorta was decellularized by 5 different protocols in groups A-E: 0.1% trypsin/0.02% ethylenediamine tetraacetic acid (EDTA)/PBS was used in group A, 1%Triton X-100/0.02% EDTA/ distilled water in group B, 1% sodium deoxycholic acid/distilled water in group C, 0.5% sodium deoxycholic acid/0.5% sodium dodecyl sulfate/distilled water in group D, and 1% deoxycholic acid/distilled water in group E; and the porcine ascending aorta was not decellularized as control in group F. The ascending aorta scaffolds were investigated by gross examination, HE staining, DNA quantitative analysis, immunohistochemistry, and scanning electron microscopy were used to observe the efficiency of decellularization, microstructure of the ECM, the damage of collagen type I and elastin, the structure of intimal surface, and biomechanical property. The 90 Sprague Dawley rats were randomly divided into 6 groups (n=15). Each scaffold was implanted in the abdominal muscles of rats respectively to evaluate the immunogenicity and biocompatibility., Results: HE staining and quantitative analysis of DNA showed that the cells were completely removed only in groups A and D. The expression of collagen type I in group A was significantly lower than that in the other 5 groups (P < 0.05), and serious damage of the basement membrane and decreased beomechanical property were observed. The maximum stress and tensile strength in group A was significantly lower than those in the other groups (P < 0.05), and elongation at break was significantly higher than that in the other groups (P < 0.05). The destruction of collagen type I was significant (P < 0.05) in group D, but the basement membrane was integrity, the biomechanical properties were close to the natural blood vessels (group F) (P > 0.05). Implantation results showed that the scaffold of group D had superior immunogenicity and histocompatibility to the scaffold of the other groups. The inflammatory reaction was gentle and the number of the inflammatory cell infiltration was lower in group D than in other groups (P < 0.05)., Conclusion: It is concludes that 0.5% sodium deoxycholic acid/0.5% sodium dodecyl sulfate/distilled water is more suitable for the decellularization of porcine aorta, by which the acquired ECM scaffold has the potential for constructing tissue engineered vessel.

The taxonomic status of a moderately halophilic bacterium, strain N4(T), isolated from soil of a chicken farm in China was determined. It was Gram-negative, non-spore-forming, motile, and rod-shaped. Phylogenetic analysis based on 16S rRNA gene sequence indicated that this strain belonged to the genus Salinicola, as it showed the highest sequence similarities to Salinicola salaries M27(T) (98.3 %), Salinicola socius SMB35(T) (98.1 %), and Salinicola halophilus CG4.1(T) (98.1 %). The major cellular fatty acids were C(16:0) (25.6 %), C(18:1)ω7c (35.0 %), and C(19:0) cyclo ω8c (11.9 %), which are properties shared by members of the genus Salinicola. The DNA G+C content of strain N4(T) was 69.1 mol %. The level of DNA-DNA relatedness between strain N4(T) and the other three type strains of the genus of Salinicola salaries M27(T), Salinicola socius SMB35(T), and Salinicola halophilus CG4.1(T) were 34.3, 28.7, and 26.9 %, respectively. Based on the results of phenotypic, chemotaxonomic, DNA-DNA relatedness, and phylogenetic analysis, strain N4(T) should be classified as a novel species of the genus Salinicola, for which the name Salinicola zeshunii sp. nov. is proposed, with strain N4(T) (=KACC 16602(T) = CCTCC AB 2012912(T)) as the type strain.